; The GIMP -- an image manipulation program
; Copyright (C) 1995 Spencer Kimball and Peter Mattis
;
; Beveled pattern arrow for web pages
; Copyright (C) 1997 Federico Mena Quintero
; federico@nuclecu.unam.mx
;
; This program is free software; you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation; either version 2 of the License, or
; (at your option) any later version.
;
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
; GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program; if not, write to the Free Software
; Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.


(define (script-fu-beveled-pattern-arrow size orientation pattern)

  ; define some local helper functions
  (define (map proc seq)
    (if (null? seq)
        '()
        (cons (proc (car seq))
              (map proc (cdr seq)))))

  (define (for-each proc seq)
    (if (not (null? seq))
        (begin
          (proc (car seq))
          (for-each proc (cdr seq)))))

  (define (make-point x y)
    (cons x y))

  (define (point-x p)
    (car p))

  (define (point-y p)
    (cdr p))

  (define (point-list->double-array point-list)
    (let* ((how-many (length point-list))
           (a (cons-array (* 2 how-many) 'double))
           (count 0))
      (for-each (lambda (p)
                  (aset a (* count 2) (point-x p))
                  (aset a (+ 1 (* count 2)) (point-y p))
                  (set! count (+ count 1)))
                point-list)
      a))

  (define (rotate-points points size orientation)
    (map (lambda (p)
           (let ((px (point-x p))
                 (py (point-y p)))
             (cond ((= orientation 0) (make-point px py))           ; right
                   ((= orientation 1) (make-point (- size px) py))  ; left
                   ((= orientation 2) (make-point py (- size px)))  ; up
                   ((= orientation 3) (make-point py px)))))        ; down
         points))

  (define (make-arrow size offset)
    (list (make-point offset offset)
          (make-point (- size offset) (/ size 2))
          (make-point offset (- size offset))))

  ; the main function

  (let* ((img (car (gimp-image-new size size RGB)))
         (background (car (gimp-layer-new img size size RGB-IMAGE "Arrow" 100 NORMAL-MODE)))
         (bumpmap (car (gimp-layer-new img size size RGB-IMAGE "Bumpmap" 100 NORMAL-MODE)))
         (big-arrow (point-list->double-array (rotate-points (make-arrow size 6) size orientation)))
         (med-arrow (point-list->double-array (rotate-points (make-arrow size 7) size orientation)))
         (small-arrow (point-list->double-array (rotate-points (make-arrow size 8) size orientation))))

    (gimp-context-push)

    (gimp-image-undo-disable img)
    (gimp-image-add-layer img background -1)
    (gimp-image-add-layer img bumpmap -1)

    ; Create pattern layer

    (gimp-context-set-background '(0 0 0))
    (gimp-edit-fill background BACKGROUND-FILL)
    (gimp-context-set-pattern pattern)
    (gimp-edit-bucket-fill background PATTERN-BUCKET-FILL NORMAL-MODE 100 0 FALSE 0 0)

    ; Create bumpmap layer

    (gimp-edit-fill bumpmap BACKGROUND-FILL)

    (gimp-context-set-background '(127 127 127))
    (gimp-rect-select img 1 1 (- size 2) (- size 2) CHANNEL-OP-REPLACE FALSE 0)
    (gimp-edit-fill bumpmap BACKGROUND-FILL)

    (gimp-context-set-background '(255 255 255))
    (gimp-rect-select img 2 2 (- size 4) (- size 4) CHANNEL-OP-REPLACE FALSE 0)
    (gimp-edit-fill bumpmap BACKGROUND-FILL)

    (gimp-context-set-background '(127 127 127))
    (gimp-free-select img 6 big-arrow CHANNEL-OP-REPLACE TRUE FALSE 0)
    (gimp-edit-fill bumpmap BACKGROUND-FILL)

    (gimp-context-set-background '(0 0 0))
    (gimp-free-select img 6 med-arrow CHANNEL-OP-REPLACE TRUE FALSE 0)
    (gimp-edit-fill bumpmap BACKGROUND-FILL)

    (gimp-selection-none img)

    ; Bumpmap

    (plug-in-bump-map 1 img background bumpmap 135 45 2 0 0 0 0 TRUE FALSE 0)

    ; Darken arrow

    (gimp-context-set-background '(255 255 255))
    (gimp-edit-fill bumpmap BACKGROUND-FILL)

    (gimp-context-set-background '(192 192 192))
    (gimp-free-select img 6 small-arrow CHANNEL-OP-REPLACE TRUE FALSE 0)
    (gimp-edit-fill bumpmap BACKGROUND-FILL)

    (gimp-selection-none img)

    (gimp-layer-set-mode bumpmap MULTIPLY-MODE)

    (gimp-image-flatten img)

    (gimp-image-undo-enable img)
    (gimp-display-new img)

    (gimp-context-pop)))


(script-fu-register "script-fu-beveled-pattern-arrow"
                    _"_Arrow..."
                    "Beveled pattern arrow"
                    "Federico Mena Quintero"
                    "Federico Mena Quintero"
                    "July 1997"
                    ""
                    SF-ADJUSTMENT _"Size"        '(32 5 150 1 10 0 1)
                    SF-OPTION     _"Orientation" '(_"Right"
						   _"Left"
						   _"Up"
						   _"Down")
                    SF-PATTERN    _"Pattern"     "Wood")

(script-fu-menu-register "script-fu-beveled-pattern-arrow"
			 "<Toolbox>/Xtns/Web Page Themes/Beveled Pattern")
